Hundreds of staff and students have signed an online petition calling for the vice-chancellor of a prominent West Wales university to resign from her post.

Professor April McMahon has come under increasing pressure in recent months, amid concerns around a fall in student numbers and Aberystwyth University’s position in league tables.

The petition, which last night had 775 signatures, cites the university’s dip in Guardian and Complete University rankings and sliding applications since her arrival in August 2011.

Data compiled by the Universities and Colleges Admissions Service (Ucas) shows Aberystwyth accepted far fewer students last September than at the same time in 2012.

The university’s intake has fallen for the past two years, from 3,310 students in 2011-12 to 2,710 students in 2012-13. Aberystwyth took on 2,520 learners at the start of the current academic year.

Earlier this month, Aberystwyth University, which has targeted a place in the top 30 universities in the UK by 2017, fell 17 places to 87th in the 2015 Complete University Guide.

The petition makes reference to Prof McMahon’s pay rise of 9.57% in 2012-13 and says her £252,000 salary and pension contributions was “in line with that of Barack Obama and almost double David Cameron’s annual salary”.

The petition adds: “Students came to Aberystwyth when it was a top 50 university and will leave with a degree from an institution flailing at the bottom of the league tables... Aberystwyth is a wonderful town and it deserves a successful, honest institution: let’s re-claim our university.”

It is the second time Prof McMahon has been the subject of a web-based petition in recent months, although the first was suspended suddenly in April having attracted 550 signatures.

Its creator, an undergraduate at the university, said he closed the petition after a meeting with the vice-chancellor and senior managers. A Scottish native and Gaelic speaker, Prof McMahon was formerly vice-principal for planning, resources and research policy at the prestigious University of Edinburgh.

A spokesman for Aberystwyth University said: “Shortly after the first petition was posted online, the creator... requested a meeting with members of the executive. Following these conversations the petition holder decided to withdraw the petition.

“The university is aware of the new petition. However, as it has been created anonymously, and as no approach for a meeting to discuss concerns has been made, the university is unable to respond. Regardless, we note that the university is held in high regard by individuals and that we agree that the future of Aberystwyth University is vitally important.”